dell

Goes the way of Fusion
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Might be unlockable as well
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Looks ready to us

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AMD's answer to GTX 550 Ti

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Barts at 975MHz

apple

Found under the bonnet of update 10.6.7
nvidia

It all comes down to price
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Custom HD 6950 FleX Edition
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Gets HD 6990, GTX 590 and GTX 550 Ti support
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All reference cards